King County Washington Energy Code Compliance
WSEC-R 2021 compliance information for builders and contractors in King County.
Code environment
Climate Zone
CZ4
Western Washington — west of the Cascade crest, marine climate.
Wall min R-20 cavity + R-5 continuous, or R-13 cavity + R-10 continuous · Ceiling min R-60 · Window max U-0.30 · WAC 51-11R-40213, Table R402.1.3
Radon Zone
Zone 2
Moderate radon potential — radon-resistant construction recommended but not mandated by state code.
Learn more →County building department
The county building department handles permits for unincorporated areas. Cities within the county may have their own permit offices — see below.
Authority Having Jurisdiction (AHJ)
Department of Local Services - Permitting Division
- Phone
- (206) 296-6600
- Address
- 919 SW Grady Way, Ste 300, Renton, WA 98057
- Hours
- M/Th 8:30am-3:30pm
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Submittal notes
- King County: King County requires a '2021 Energy Compliance Summary Sheet' specifying exact HVAC equipment specs (mini-splits ≥10.0 HSPF, air-to-water heat pumps ≥3.2 COP at 47°F), hot water loop volumes (≤16 oz between source and fixture), and solar-ready provisions.
- Seattle: Seattle: Third-party blower door test results must be physically posted near the electrical panel before final inspection.
- Bellevue: Bellevue layers the 2023 Washington Cities Electrical Code on top of WSEC-R 2021 — additional lighting budget calculations and heat system sizing forms are required beyond other MBP-consortium jurisdictions.
- Redmond: Redmond requires environmental checklist and critical areas report (SEPA) clearance before the building permit can issue.
Cities with their own building department
These cities have an independent permit office. If your project is inside city limits, contact the city — not the county — for permits.
Auburn
Auburn Community Development
- Phone
- (253) 931-3090
- Address
- 25 W Main St, Auburn, WA 98001
- Hours
- M-F 8am-5pm
- Website
- https://www.auburnwa.gov/
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Bellevue
Bellevue Development Services Permit Center
- Phone
- (425) 452-4898
- Address
- 450 110th Ave NE, Bellevue, WA 98004
- Hours
- M-F 8am-4pm
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Bothell
Bothell Community Development Department
- Phone
- (425) 806-6400
- Address
- 18415 101st Avenue NE, Bothell, WA 98011
- Hours
- M-F 8am-5pm
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Burien
Burien Community Development Department
- Phone
- (206) 241-4647
- Address
- 400 SW 152nd, Ste 300, Burien, WA 98166
- Hours
- M-F 8am-5pm
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Federal Way
Federal Way Community Development
- Phone
- (253) 835-2607
- Address
- 33325 8th Ave S, Federal Way, WA 98003
- Hours
- M-F 8am-5pm
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Issaquah
Issaquah Development Services Department
- Phone
- (425) 837-3100
- Address
- 1775 12th Ave NW, Issaquah, WA 98027
- Hours
- M-F 8am-5pm
- Website
- https://www.issaquahwa.gov/
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Kenmore
Kenmore City Hall
- Phone
- (425) 398-8900
- Address
- 18120 68th Ave NE, Kenmore, WA 98028
- Hours
- M-F 8am-5pm
- Website
- https://www.kenmorewa.gov/
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Kirkland
Kirkland Planning and Building
- Phone
- (425) 587-3600
- Address
- 123 5th Ave, Kirkland, WA 98033
- Hours
- M-F 8am-5pm
- Website
- https://www.kirklandwa.gov/
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Mercer Island
Mercer Island Community Planning & Department
- Phone
- (206) 275-7605
- Address
- 9611 SE 36th St, Mercer Island, WA 98040
- Hours
- M-F 8am-5pm
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Newcastle
Newcastle Community Development/Permits
- Phone
- (425) 649-4444
- Address
- 12835 Newcastle Way, Ste 200, Newcastle, WA 98056
- Hours
- M-F 8am-5pm
- Website
- https://newcastlewa.gov
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Sammamish
Sammamish Permit Center
- Phone
- (425) 295-0531
- Address
- 801 228th Ave SE, Sammamish, WA 98075
- Hours
- M-F 8:30am-5pm
- Website
- https://www.sammamish.us
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Seattle
Seattle Department of Construction and Inspections
- Phone
- (206) 684-8600
- Address
- 700 5th Ave, Seattle, WA 98104
- Hours
- M-W-F 8am-4pm
- Website
- https://www.seattle.gov/sdci
- Notes
- independent portal
Last verified: 2026-04-19
Snoqualmie
Snoqualmie City Hall
- Phone
- (425) 888-5435
- Address
- 38624 SE River St, Snoqualmie, WA 98065
- Hours
- M-F 8am-5pm
- Portal
- Online permit portal →
- Notes
- uses MyBuildingPermit.com
Last verified: 2026-04-19
Not listed? Your project is in unincorporated King County — use the county building department above.
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Answer a few questions about your project and get a complete R406 credit summary you can submit with your permit application.
Start your WSEC compliance check →Typical project costs in King County
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